Update QR Code and Fix Minor Typo

[MooooCat]

Description

• Updated the Wechat Group QR code link and image in both README.md and README_ZH_CN.md to point to the new file assets/live_QR_code.jpg.
• Adjusted the width of the Wechat Group QR code image in README_ZH_CN.md to maintain consistency.
• Fix typo.

Motivation and Context

• The typo correction improves the readability.
• Ensuring the QR code image size is live.

How has this been tested?

• Verified that the new QR code image is clear and functional.

Types of changes

• Maintenance (no change in code, maintain the project's CI, docs, etc.)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.